Many designs of plastic buckets and lids are well-known, see for example the following patents of John W. Von Holdt: U.S. Pat. Nos. 4,375,948; 4,574,974; 4,512,494; 4,512,493; 4,452,382; 4,380,305; 4,308,970; and 4,210,258.
Many containers, such as cans for food, paint and other solvents and chemicals have also been made of plastic, as shown in the above-cited patents. However, plastic buckets of course lack the strength of metal buckets, so that in many cases special designs of the plastic buckets must be used to obtain, for example, a desired level of hoop strength about the mouth of the plastic bucket. This hoop strength is achievable in the prior art by reinforcement in some manner of the mouth area of the plastic bucket, typically involving an annular portion that projects radially inwardly, which reinforces the bucket.
However, buckets of this design typically require a collapsible core for their molding, which adds capital and operating expense to the operation, and also tends to slow the operation down. Likewise, collapsible cores are subject to failure and other problems, which further slows the efficiency of the operation.
In accordance with this invention, a plastic bucket is provided which does not require manufacture by the use of a collapsible core. At the same time, the bucket has a desired amount of hoop strength, even a plastic bucket which is of the shape of a conventional metal paint can.